Clematis plant named ‘Zobast’

ABSTRACT

A new cultivar of hybrid  Clematis , ‘Zobast’, characterized by its upright, star-shaped, single to occasionally double flowers that are white in color, its ability to bloom in spring and even more abundantly in summer, its near sterility, and its cold hardiness to at least U.S.D.A. Zone 6.

Botanical classification: Clematis hybrid.

Variety denomination: ‘Zobast’.

CROSS REFERENCE TO A RELATED APPLICATION

This application is co-pending with a U.S. Plant Patent Application filed for a plant derived from similar parentage that is entitled Clematis Plant Named ‘Zobadol’ (U.S. Plant patent application Ser. No. 13/385,252).

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Clematis, botanically an interspecific hybrid (Patens group), and will be referred to hereafter by its cultivar name ‘Zobast’. ‘Zobast’ is grown as an herbaceous climbing plant for use in the landscape or as a flowering potted plant for the terrace.

‘Zobast’ derived from an ongoing breeding program by the inventor in his nursery in Boskoop, The Netherlands. The goal of the selection was to select a cold hardy climber with a dwarf habitus that could be grown for different purposes in the garden.

‘Zobast’ arose as a seedling derived from open pollination of an unnamed plant from the breeding program, designated as No. 19960074 in 2003. ‘Zobast’ was selected as a single unique plant from the batch of seedlings in 2006.

Asexual reproduction of the new cultivar was first accomplished by internodial stem cuttings under the direction of the Inventor in Boskoop, The Netherlands in 2006. The characteristics of this cultivar have been determined to be stable and are reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and represent the characteristics of the new cultivar as grown outdoors and observed for five years in Boskoop, The Netherlands. These attributes in combination distinguish ‘Zobast’ from other varieties of Clematis known to the Inventor.

-   -   1. ‘Zobast’ exhibits upright flowers that are white in color.     -   2. ‘Zobast’ blooms in spring and even more abundantly in summer.     -   3. ‘Zobast’ exhibits flowers that are star-shaped, they are         typically single but the first flowers may be double in spring         (double flowers stand solitary and terminal on the shoot).     -   4. ‘Zobast’ is more or less sterile; seed is barely produced.     -   5. ‘Zobast’ is cold hardy to at least U.S.D.A. Zone 6.         ‘Zobast’ differs from its female parent, No. 19960074, in having         white flowers rather then violet-blue, and in having a much more         floriferous habitus. ‘Zobadol’ differs from ‘Zobast’ in having         light violet flowers and in only having single flowers.         ‘Zobast’ can be most closely compared to the cultivars ‘Huldine’         (not patented) and ‘The Bride’ (not patented), differences are         described in TABLE 1.

TABLE 1 Characteristic Comparison cultivar ‘Zobast’ ‘Huldine’ Tepal shape Oblong with obtuse Ovate with acute apex apex ‘Huldine’ Tepal color at White with pink White with white lower surface centers centers ‘The Bride’ Tepal shape Broadly ovate with Ovate with acute obtuse apex apex ‘The Bride’ Flower shape Always single First flowers may be double

BRIEF DESCRIPTION OF THE DRAWING

The accompanying colored photographs illustrate the overall appearance and distinct characteristics of the new Clematis. The photographs were taken of three year-old plants of ‘Zobast’ as grown in one-gallon containers in Boskoop, The Netherlands.

The photograph in FIG. 1 shows the flowering habitus.

The photograph in FIG. 2 shows the back of the flower.

The photograph in FIG. 3 shows the inside of the flower with a close up of the stamens and pistils.

The photograph in FIG. 4 shows the flower buds.

The photograph in FIG. 5 shows the seedhead.

The photograph in FIG. 6 shows the lower surface of the leaves and the photograph in FIG. 7 shows a double flower.

The colors of the photographs are as close as possible with the digital photography techniques available, the color values cited in the detailed botanical description describe the colors as accurately as possible of the new Clematis.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of three year-old plants of Clematis ‘Zobast’ as grown outdoors in one-gallon containers under full sun at a nursery in Boskoop, The Netherlands. The phenotype of the new cultivar of Clematis may vary with variations in environmental, climatic and cultural conditions as the cultivar has not been tested under all possible environmental conditions. The color determination is in accordance with The 2001 R.H.S. Colour Chart, London, England, except where general color terms of ordinary dictionary significance are used.

-   General description:     -   -   Botanical classification.—Clematis ‘Zobast’ (classified in             the Patens Group).         -   Blooming period.—Blooms for 4 to 6 weeks in spring and more             abundantly in summer for 6 to 8 weeks.         -   Plant habit.—Herbaceous climber.         -   Height and spread.—Three year-old plant is about 15 cm at             the base with a height of about 1.5 m height when pruned             after the first flowering.         -   Cold hardiness.—At least to U.S.D.A. Zone 6.         -   Culture.—Moist but well-drained soil in full sun with the             roots shaded.         -   Diseases and pests.—No resistance to wilt had been observed.         -   Root description.—Fleshy. -   Growth and propagation:     -   -   Propagation.—Internodial soft wood cuttings from vegatative             shoots.         -   Root initiation.—Roots develop in 6 weeks in summer under             greenhouse conditions.         -   Time required for root development.—75 to 90 days to develop             a 5-cm container from a 5-cm cutting.         -   Growth rate.—Moderately vigorous once planted out. -   Stem description:     -   -   Shape.—Round and 6-ribbed.         -   Stem color.—N77A.         -   Stem size.—About 1.5 m (including peduncle and terminal             pedicel) in length, an average of 2 to 3 mm in diameter.         -   Stem surface.—Covered in sparse short hairs but more densely             so near the nodes.         -   Internode length.—Ranges from 4 to 6 cm.         -   Branching.—Basal branches. -   Foliage description:     -   -   Leaf arrangement.—Opposite.         -   Leaf division.—Ternate.         -   Leaf size.—Up to 10 cm long and 7 cm in width.         -   Leaf attachment.—Petiolate.         -   Leaflet shape.—Elliptic.         -   Leaflet base.—Obtuse.         -   Leaflet apex.—Acute.         -   Leaflet fragrance.—Fresh “green” fragrance when crushed.         -   Leaflet venation.—Just slightly reticulate at upper surface,             lower surface slightly reticulate.         -   Leaflet margins.—Entire.         -   Leaflet attachment.—Petiolulate.         -   Leaflet surface.—Upper surface glabrous with a few hairs on             the main veins; lower surface sparsely hairy with main veins             more densely so.         -   Leaflet size.—Up to 5.5 cm in length and up to 3 cm in             width.         -   Leaflet color.—Upper surface 147A, lower surface 147B.         -   Petioles and petiolules.—Petiole up to 4 cm in length and             about 3 mm in width, 146B in color, sparsely hairy;             petiolule 0.7 to 1.2 cm in length and about 2 mm in width,             146B in color, surface is a bit articulate and sparsely             hairy on both. -   Inflorescence description:     -   -   Inflorescence type.—Solitary or 3-flowered dichasial cyme.         -   Inflorescence arrangement.—Terminal and axillary on young             shoots.         -   Peduncles.—3 to 4 cm in length, 144A in color and may be             suffused with 187A, round and just slightly 6 ribbed in             shape, surface covered in sparse short hairs.         -   Pedicels.—3 to 5 cm in length, 144A in color, round in             shape, surface covered in sparse short hairs.         -   Peduncle bracts.—Leaf-like but simple.         -   Flower bud description.—Held upright, ovate at first but             later lanceolate in shape, 144B in color with seams 155B and             slight bit of 59B at the apex, apex acuminate, base obtuse,             surface covered in sparse short hairs with very short hairs             on seams.         -   Flower fragrance.—None.         -   Lastingness of the flowers.—Individual flowers last up to             about 10 days until the first tepal drop followed later by             the stamens.         -   Flower quantity.—Solitary flowers or in a 3-flowered             dichasial cyme, terminal and axillary on young shoots, about             30 to 50 flowers in spring and 50 to 70 flowers in summer on             a 3 year old plant.         -   Flower type.—Spreading, single but on an established plant             the first flowers might be double (in which case they are             solitary on terminal).         -   Flower aspect.—Upright facing.         -   Flower size.—Range from 5 to 8 cm in diameter and about 3 cm             in depth.         -   Flower sex.—Bisexual.         -   Tepal number.—Usually 5 or 6 in number but sometimes 4 on             single flowers, an average of 22 on double flowers             (including staminodes that are similar to characteristics to             tepals).         -   Tepal shape.—Elliptic.         -   Tepal apex.—Acute.         -   Tepal base.—Cuneate.         -   Tepal margin.—Entire.         -   Tepal surface.—Upper surface; glabrous, lower surface;             hairy, margin glabrous but heavily covered in short hairs             towards middle.         -   Tepal color.—Upper surface; whiter than 155A with a             occasional marking of 157A, especially near base and on             midrib; lower surface 155A with small lines in midrib of             157A extending to base.         -   Tepal and staminode size.—Up to 4 cm in length and 2.5 cm in             width. -   Reproductive organs:     -   -   Gynoecium.—Numerous pistils (about 30 to 40), 1.2 cm in             length, style a blend of 155A and 145D, ovary 144B, stigma             158B, rather thin and slightly reflexed.         -   Androcoecium.—Filaments are 0.4 to 1 cm in length and 1 mm             in width, linear, 155B in color, glabrous surface, anthers;             4 mm in length, linear, 155A; connective not elongated, 155A             becoming 202A; in spring flowers some tepal-like staminodes             which gives the appearance of a double flower, whiter than             155A in color with midrib 144B on upper and lower surface,             apex acute to emarginated, similar in characteristics to             tepals.         -   Seed.—Head; to 5 cm in diameter, style; up to 3 cm in             length, 144C in color with hairs 161C, ovary; 144B in color             with a hairy surface, stigma; 145B in color, just a bit bent             to almost straight with tip 161B in color, seed; more or             less sterile; seed is barely produced. 

It is claimed:
 1. A new and distinct cultivar of Clematis plant named ‘Zobast’ as herein illustrated and described. 